Centrifugal casting apparatus



R. C. MYERS CENTRIFUGAL CASTING APPARATUS Nov. 3, 1953 6 Sheets-Sheet 1 Filed May 13, 1949 R. 0 m m m zoberiaf'f 6376,

Nov. 3, 1953 R. C. MYERS CENTRIFUGAL CASTING APPARATUS 6 Sheets-Sheet 2 Filed May 13, 1949 INVENTOR. fiaberi C/Ygens,

Nov. 3, 1953 R. c. MYERS CENTRIFUGAL CASTING APPARATUS 6 Sheets-Sheet 3 Filed May 13, 1949 & Y

INVENTOR. J20 eri CJYyera, Y 59%;,

E g mm, m% M Nov. 3, 1953 R. c. MYERS CENTRIFUGAL CASTING APPARATUS -6 Sheets Sheet 4 Filed May 15, 1949 INVENTOR. EOerL 5 Nov. 3, 1953 R. c. MYERS CENTRIFUGAL CASTING APPARATUS 6 Sheets-Sheet 5 Filed May 13, 1949 m m m m berZ C/Zgens,

Nov. 3, 1953 R. c. MYERS 2,657,440

CENTRIFUGAL CASTING APPARATUS Filed May 15, 1949 6 Sheets-Sheet 6 mw u a m A u m Patented Nov. 3, 1953 CENTRIFUGAL CASTING APPARATUS Robert C. Myers, Cambridge City, Ind, assignor to Perfect Circle Corporation, Hagerstown, Ind., a corporation of Indiana Application May 13, 1949, Serial No. 93,010

6 Claims.

The invention relates generally to apparatus for making centrifugal castings and more particularly to such apparatus for making hollow cylindrical castings.

The general object of the invention is to provide novel centrifugal casting apparatus of the foregoing character, by which continuous manufacture of castings may be performed.

Another object is to provide novel centrifugal .casting apparatus of the foregoing character, by

which high quality castings may be made, and which provides for accurate control of the various factors resulting in the high quality.

A further object is to provide novel apparatus for making centrifugal castings, in which dies or parent from the following description taken in connection with the accompanying drawings, in

which:

Figure 1 is a front elevational view of the centrifugal casting apparatus embodying the fea tures of the invention, with parts of the apparatus broken away.

Fig. 2 is an end elevational view of the righthand end of the apparatus as shown in Fig. 1.

Fig. 3 is a rear elevational view of the apparatus, with parts thereof broken away.

Fig. 4 is a vertical sectional view taken substantially on the line 4-4 of Fig. 1.

Fig. 5 is an enlarged fragmentary horizontal sectional view taken substantially on the line 5-5 of Fig. 1.

Fig. 6 is an enlarged fragmentary horizontal sectional view taken substantially on the line 66 of Fig. 4.

Fig. 7 is an enlarged fragmentary elevational view of a portion of the apparatus shown in Fig. 2.

Fig. 8 is an enlarged longitudinal sectional view of one of the dies utilized in the apparatus and illustrating one of the steps in the process of cast- Fig. 9 is a view similar to Fig. 8 but illustrating another step in the process of casting.

Fig. 10 is a perspective view of one of the dies illustrated in Figs. 8 and 9, with the parts thereof separated.

Fig. 11 is an end view of the right-hand end of one of the dies as illustrated in Fig. 10.

The present apparatus is of the type in which the metal is cast in permanent cylindrical metal dies rotatably driven during the pouring of the molten metal to uniformly distribute the metal Within the die and to maintain such distribution until the metal has solidified. The amount of metal poured into each die thus determines the thickness of the casting. During the casting of the metal, the die is protected from direct contact with the molten metal by an insulating coating placed on the interior of the die, prior to the pouring of the molten metal. Such insulating coating not only protects the die from the heat of the metal but also assists in controlling the cooling rate of the casting so that a desired metallurgical structure may be obtained in the casting. The coating also facilitates the ejection of the casting from the die after it has solidified and cooled to the desired extent.

For these broad purposes, the present apparatus comprises generally a casting section, an ejector section, and a storage section intermediate the other two sections. In the casting section, a die is placed on a rotary driving means for rapidly rotating the die to effect the centrifugal action. While the die is being so driven, a coating is placed on the interior of the die and thereafter molten metal is poured into the die in the desired quantity to form the casting. Spinning .of the die is maintained during this procedure and continued thereafter until the casting has sufficiently solidified to maintain its shape, during which period the desired metallurgical structure is attained.

The die is then removed from the rotary driving means and passed through the intermediate storage section of the apparatus where the casting cools in a controlled manner to bring it to a suitable temperature for removal from the die. From the intermediate storage section, the die with the casting therein passes to the ejector section where the casting is removed from the die. After ejection of the casting, the empty die is then moved again into the storage section, where its temperature is brought to a desired point and it is held in readiness for admission to the casting section for making another casting. It is, of course, to be understood that while only one die is admitted to the casting section. at any one time and only one die is permitted to enter the ejector section at one time, a series of dies is held in the storage section, some having castings therein which are cooling while others are empty and are held in readiness for introduction to the casting section.

General description of the apparatus The dies, as heretofore mentioned, are of a. permanent character made of metal and are cylindrical in form. The construction of each die is such that, whileboth ends of the die are open, the openings are of smaller diameter than the inside diameter of the die so that, when the molten metal is poured into the die, the spinning movement holds the metal against the die, evenly distributed therein and none will run out the ends of the die. To permit removal of thesolidified casting, one end of the meme arernoya ble portion in the form of a cap, permitting the casting to be slid out of that end when the cap is removed.

In the particular form. illustrated in the drawings, each die comprisesa bedy l2 (see Figs 3, 9, 10 and I l) whichis cylindrical both interiorly and exteriorly throughout its length. Qne end of the body [2, in this instance the rear end, is provided with a cap l3 permanently secured to the b d as y rews an having cen a ave ture M. The diameter oftheaperture I4 is les s than the inner diameter'of the casting so that themolten metal will not run out the end or the die.

' The other end of the body I2 is provided with I the body l2 asby screws. The cap" l5 and retainingf ring l6 are heldftogether by meansof segmental lugs I! on the caps (see Figs. 10 and ii) engageable under segmental lugs ill on the ring is. Asis apparentfthe lugsd'l may be disengaged from the lugs l8 by rotating the cap I5 relative to the ringlli'to permit removal of the cap. The cap I5 is: also provided with a pair of lugs IS on its face, which may be engaged by a suitable spannr wrenchinotshownl for rotating the cap;

The apparatus, as illustrated in the drawings, is in the form'of an elongated housing comprising 'a casting section, indicated generally at 2-0 (see Figs. 1", 2', 3 and 5) {an ejector'section, indicatedge'nerally at'Z-I (see Figs. 1 3-, 4'and6) and an intermediate storage section, indicated genorally at 22. The housing comprising the three sections named is generally constructed of plate and angle members; In the intermediate "section 22 are conveying means, herein shown, in the form: of tracks "which'are' slanted suificiently to cause the dies to roll-between the casting section and the ejector section =21, while izithe latter'two 'sectio'nsthere are transfer devices in the form of elevators for shifting the dies. Thus, as shown in Figs. 1 and 3, an upper track 23 is provided for conveying the dies in onedirection through the intermediate section 22, while a lower track -2 4-is providedfor oonveying-thedies in the opposite direction. Thelfrontfacaotthe intermediate section 22 preferably comprises. a series of hinged doorsto permit, access to the interior of. the intermediatesection whendesired. In the casting section it, isa,.diesupportingand t n m an n ma e genera l t 25 e F 2 3 5 nd. siti ned diese lower. track. Also} maunted infthe casting section 20 is'ian eleVatorfZB errangedtq transferdies between the die 'rotating mean/s25.,andthetupper track 23. In the ejector section .2l is an ejector, indicatedgenerally at 2 (see Figsl, 3,; 4 and G) for removing'the castings from the dies, thefejector 21 being preferably mounted at the level" of 4 the lower track 24. Also mounted in the ejector section 2i is an elevator, indicated generally at 30, for moving the dies between the level of the ejector 21 and the upper track 23.

Mounted on the casting section 20, in the present instance at the rear side thereof, is a means,

indicated generally at,3l ,.fcr applying a coating to the interior of the die. see Figs. 2 and 7), such coating being preferably in liquid form and, therefore, capable of being applied by means of a spray. The casting section also includes means,

indicated generally at 32 (Fig. 2) for measuring ,and pouring a-quantity of molten metal into a die positioned or 'the supporting and rotating niee s i The casting section 20 inspection of Fig, 5, and are supported in bearings carried in roller supports 34. Thevlatter are provided with base portions 35 slidably mounted and guided on rails 36 rigidly secured in and forming a part of the housing structure of the casting section 2]]. The slidable mounting of the base portions 35 is provided so that rollers of eachpair may be adjusted toward and from each other toaccommodatedies of different diametersythe die resting peripherally on-the rollers. Preferably, the pair of rollers 33 at the front of the machine are slightly larger in diameter than the rollers at the rear of the machine so as t fit within a peripheral-groove 31 (see Figs. Zand- 8-) provided in the die to prevent endwise movement of the die relative to the rollers 33.

Adjusting means is provided for shifting the rollers 33- of each pair toward and from each other, such adjusting means being arranged to adjust. all four rollers simultaneously in equal amounts. To this end, the base portion 35 of each roller support 34 is provided with a downwardly extending lug '40 (see Fig. 5) having threaded engagement with a screw H. The threaded portions of each screw 4| are of opposite hand so as to eifect adjustment ofthe rollersof each pair towardand from each other. The screws M of the two pairs of rollers extend to the ext'erior of the casting section 20 and on their, outer ends are provided with sprockets 42 (see-Figs. 2 and 5) connected by a chain 43- so that, by turning one sprocketboth screws 4| will be rotated and all four-rollers 33 thus adjusted simultaneously.

The front pair of rollers 33, in the present instance, are shown as merely idler'rollers, while the rearpair of rollers 33 are adaptedto be rotatably driven To this end each'rear roller 33-is mounted 0n a shafttdisee Fig. 5) extending rearwardly to the exterior of the casting section 2l andhaving a pulley-d5 (see Figs. 3 and 5) mountedgon the outer end of the shaft. A motor 46 is providedfor drivin the rollers 33 and is connected by a belt 47 to a driven pulley of a speed-reducing unit 50. The speed-reducing unit 50 also ha a drive pulley 5| connected by a belt 52 to the pulleys 45. A belt tightening pulley 5; is preferably provided, the pulley 53 being mountedbetween and below the pulleys 45 and carried on a pivoted-lever 54 adjustably secured to the rear wall of the casting section 20-.

The empty dies are adapted to be admitted one at a time to the casting section 20 and the latter is separated from the storage section 22 by a door 60 (see Figs. 1, 3 and 5). The door in the present instance is shown as being vertically movable and is adapted to be shifted by a hydraulic actuator 6| (see Figs. 1 and 3). By means of the actuator BI, the door 60 may be lowered when it is desired to admit a die from the storage section 22 to the casting section 23 for positioning on the rollers 33. While the apparatus could be arranged to store the empty dies on the upper track, in the present instance the empty dies are held on the lower track 24 in the storage section 22. Since the lower track 24 is shown as terminating at the door 63, a'supporting means forming a continuation of the track 24 is provided to carry the die from the track over to the rollers 33. To this end, the door 63 is provided at its upper end with a pair of die supporting arms 62, which, when the door 60 is lowered, are at the same level as the adjacent end of the track 24, and which extend over to the rollers 33 to provide for movement of the dies from the tracks 24 to the rollers. The track 24 is preferably provided with an end portion 33 (see Figs. 1 and 3) which is more steeply inclined than the remainder of the track so that the end die will readily roll onto the arms 62 and thence onto the rollers 33. The remaining dies carried on the track 2 are held against rolling at this time by a detent 34.

After the casting has been formed and suinciently solidified to permit stopping rotation of the die, the latter is adapted to be lifted from the rollers 33 to the level of the upper track 23 and then shifted onto the upper track for movement to the ejector section. To this end, the elevator 26 is of such construction that it is movable into the space between the pairs of rollers 33 before a die is placed on the rollers. After the metal has been poured into the die and solidified, the elevator 26 is raised to carry the die with the casting therein to the level of the track 23, at which time a shifting device constituting part of the elevator 23 is provided for shifting the dies oil the elevator and onto the track 23. I

As shown in Figs. 1, 2, 3 and 5, the elevator comprises a horizontally extending arm 65 movable into the space between the pairs of rollers 33. The arm (i5 is adapted to be lowered into position between the rollers 33 before a die is placed on the latter, and, when elevated, the arm 65 extends adjacent and at the level of the track 23. Mounted within the arm 65 is a member 66 pivotally supported intermediate its ends, as at 61, by the arm 65. At its left end, as shown in Figs. 1 and 5, the member E6 is provided with a roller adapted to engage an angular stop member 'H provided within the casting section. As the arm 65 moves upwardly, the roller 'Hl contacts the stop member ll and the member 66 is caused to swing about its pivotal support 61, so that its opposite end swings upwardly and shifts the die off the elevator, and onto the track 23.

The arm 65 is carried on a vertically extending frame structure provided with rollers operating in vertically extending guideways 12 provided on the interior of the end wall of the casting section 20. To provide for the various thrusts to which the arm 65 is subjected, there are four rollers 14, two on each side of the arm 35, which are mounted on axes extending parallel to the arm 65, and four rollers mounted on axes extending transverse to the arm 35. The arm is provided with a lug 16 extending through the end wall of the casting section, and exteriorly thereof is mounted a hydraulic actuator ll connected to the lug 16. Thus by means of the actuator 11, the elevator arm 65 may be raised and lowered to lift the dies from the rollers 33 to a position adjacent the upper track 23. As the elevator reaches its upper position, the pivotally supported member 66 contacts the stop ll to shift the die off the elevator and onto the track 23.

As heretofore mentioned, the casting section 23 also includes the means 3! for coating the interior of the die with an insulating composition. Such composition is preferably an aqueous mixture so that it readily may be sprayed, and includes a refractory material, such as silica flour, and a binder therefor, such as bentonite. The mixture is adapted to be sprayed under pressure onto the interior of the die to form a coating therein of substantially uniform thickness.

The coating applying means 3| comprises a spray nozzle 83 (see Figs. 2 and 8) mounted on the end of a pipe 3| and adapted to be inserted through aperture I l in the cap l3 on the die and into the die and then moved endwise thereof to apply the spray to the interior surface of the die throughout the length thereof. Thus, the coating'applying means 3| includes means for moving the spray longitudinally of the die and, in the present instance, this means also includes an automatic control for the spray. In the preferred form, the pipe 8| is adapted to extend through an aperture 32 in the rear wall of the casting section to position the nozzle 33 within the die. The pipe 3| extends from a spray gun, indicated generally at *83 (see Figs. 2 and 7) rigidly carried on a carriage 8d. The carriage 86 is slidably mounted on a bracket 35 rigidly secured on the rear wall of the casting section 20 and extending rearwardly therefrom. The carriage 8:5 is connected to the movable member of a hydraulic actuator 83, also supported by the rear wall of the casting section.

The carriage 8 3, in the preferred arrangement, is adapted to be moved toward the rear wall of the casting section to move the nozzle 86 through the aperture 82 and into the die until it reaches the front end thereof. t that time, the trigger of the spray gun, indicated at 87, is adapted to be automatically actuated to its on position to start the spray. While the trigger remains in spraying position, the carriage E i is moved rearwardly to move the spray lengthwise within the die, as illustrated in Fig. 8, to form a coating 38. At the point in the rearward travel of the carriage when the spray reaches the rear end of the die, automatic means is provided for shutting off the spray and the carriage 81; then continues its movement until the nozzle is withdrawn through the aperture 32 to the position shown in Fig, 2. To this end, the trigger 87 is adapted to be moved to its spraying position by a finger 93 pivotally mounted on the carriage 8d. The trigger 81 is of the type that is spring-pressed to its off or non-spraying position, so that a positive force is required to actuate the finger 90. Such force is obtained by movement'of the carriage 84, which brings the finger 95 into contact with an adjustable stop screw 9| extending from a portion of the carriage supporting bracket 85. When the stop screw 9! shifts the finger Q0 to move the trigger to spraying position, a latch 92 pivotally mounted on the carriage 34 drops downwardly to position a lug 93 on the latch behind the finger 96 to hold it in such position. At this point, the carriage 84 starts to move outwardly 7 land. the itriggers' 8:7:rremains1 in spraying position alluring. this period of movement.

f Intermediate therends of .the: carriage, support- -ingvbracketrfli isa cam M'arranged to release the latch: 92 from thexfinger 90 so-that the trigger 87 maycbe e retu-rnedr to its: non-spraying. position "undenzthednfluence; of wits spring. Thus, .the lat-0112592 has; at its-end opposite .thenlug. .951, a

curved; enlarged :portion 95 adapted to be :en- -ga'ged byathe. cam 94 in'the movement'of the -'::09lrI- iag-B4.LLT11B cam-194 depressesthe end 95 "of the latch; 92. toI-lift: thexlug' 93; out of engageme'nt' with the finger: 9G. The spring actuation o f the trigger til-thereupon shifts the trigger to non-spraying position. ..-.This operation takes,

'place at the-atimathatthe spray 89' has reached 'thezmear end of the :die.v Movement of the. car- 'sr iag'e flcontinues beyond; such, point to move the spray-erearwardlythroughthe aperture 82 to an out-of-the-way non-operative position, as shown m Fig. 2.

'The device 32 for measuring and pouring a predetermined quantity ofrnolten-smetal into the die is preferably positioned at the front of the cast- *ing sectio'n 28.. Inthe present instance, the'de- 'v-ice 32- comprises a bracket .iiiii (see Fig. 2) mounted on a door 1G! pivotally supported for swingingmovement on a vertical axis bya hinge 1 02. The bracket extends forwardly from the "door -l B l when thezlatter is in closed position, and has a 'guideway'l63 engageable by rollers ltd supporting a carriage] 05. The carriage I 35 thus may be moved toward and from the door m1. Bivotally supported onthe carriage, on a hori- '-zontal axis extending parallelv tethe door, is a pouring spout lflt having'a nozzle It? insertable 'ithrough an aperture Hi8 (see Fig. 1) in the door 10i to permit the nozzle ill? to be inserted through the aperture in the cap it and into the front end of the die; By movement of the carriage- T5, the nozzle 1 El! thus may be moved into the die for pouring purposes and thence moved away from the die to permit the latter to be move'd from the supporting rollers 33. Thexpivotal mounting of pouring spout I36 permits adjustment ofthe nozzle lill for dies of different diameters, and in this connection a stop screw 99 a is \mounted in the carriage Hi5 under the pouring spout 106 to hold it in itsadjusted position. The marriage I05 also is provided with "uprights -I I9 pivotallyu supporting a frame: H19 in which a :aneasuring ladle ill is mounted. Theladle thus .:may.be tilted to :pour. molten metal therefrom into: the pouring spout I 86. Preferably, the .ladle 211 l is balan'ced so that it normally rests in.up-

prrightoposition and 'must bemanually moved by :vmeans of a handle I I2 formed on thefrarne I69, :towpour the metal therefrom intothe pouring sspout 106.

2 The foregoing construction of the casting sec-.

's'tion' 20 thus provides for shifting a die from the :lower track onto the driving and supporting 1' rollerstiwhen the door-6il between thecasting rsection and intermediate section is. lowered. During such'passage of the die, the arms E2 sup- .'port the-die in the space between theend por- --t i0n 63 of the lower track 24 and the rollers 33. At the time that thedie is placed on the rollers '33, theelevator 26 is in its loweredposition with the arm'65 lyingbelow thedie and between the:

*rollers. The motor 46 is then started to operate the rollers 33 and thus set-thedie into spinning motion aboutsits axis,

When'the die vgets up to. speed, the spraying 2 means 31 isactuated to-moveithe nozzle into the 8 die ton-the front'end-thereof. .Whenitreaches that point,-the trigger 81 ofthe spraygun 83 is automatically actuated bytthe-stop screw. 9| to start the spray. The carriage 84' carrying the spray gun 83 is then-moved rearwardly while the -spray is operating to coatthe interior of the .die with the insulating composition, as illustrated in Fig. 8. 'The spinning movement of the dieduring this time, of course, holds thespraying composition against the interior surface of the die,v and the heat of the die quickly dries thecomposition to:leave the refractory coating 88 on the interior thereof. When theispray nozzle 86 reaches the rear end of the die, the trigger 8'! is released by :the-cam 94 to stop the spray, the-carriage-Bd, however, continuing its rearward movement-t0 move the nozzletll to an inoperative position clear of the die.

At this point, the desired quantity. of. molten ,metal iscarried from a nearby melting furnace and is poured into the ladle III. The ladle Ill having a given capacity thus determines the amount of -metal to be poured into-the die and thereby-ultimatelydetermines the thickness of the casting. When the ladle iii is filled to the :desired point, the carriage I05 is movedafor- "wardly to-insert the nozzle Nil of the pouring spout me into the front end of the die, as shown inFig. 9. The carriage W5 may, of'course, be moved forwardly before the molten metal is poured into the ladle Ill, if desired. fhe ladle i l I may then be tilted by the handle l 12 to pour themolten'metal from theladle into the pouring spout m6 and thence into the die. .The molten metal received from the nozzle I01 spreads evenly over. the interior surface of the coating-asindicated at N8 in Fig. 9, andthus forms the casting, the spinning movement of the die, ofcourse, maintaining the molten metal in a-trul-y. cylindrical-shape until such time as the metal solidifies. After themetal is poured, the carriage I05 is movedaway from thedoor ill! to remove the 1 nozzle Hi! from the'die.

When the metal withinthe die has solidified sufliciently to maintain its shape, thev motor 46 is stopped to stop rotation of the rollers 33.- The elevatorv 26 is then actuated to lift the die off the rollers 33 and raise it to apposition level with. the .uppentrack 23.. As the elevator 26 approaches its .upperposition, the roller 70 on the end of the arm 6.6 contacts thestop member H to" tilt the armfit and thus shift the, die ontothe track 23.

" The 'ey ector section 21 then to the ejector section-2 ifor removal of the castings-from the dies. To this end, the upper track 23 extends into the ejector section, as shown in Figs. 1 and 3, and when the casting has "cooled sufficiently, a die with the casting-therein is lowered by means of the elevator 36 from the track 23 and then moved to'the ejector 27. As in the case of the elevator 25 in the casting-sec- 'tion 26, the elevator 36 is actuated by a hydraulic actuator 120. When-each die is thus lowered, it

1 is placed'on a short horizontal track i2i, along I which it may be rolled to the ejector 27.

The "ejector 27 comprises generally V-shaped supports forthe die'adapted to receive the castingffrom the track section lZl.

After a. die is -=placed on such V-shaped supports, the cap it is removed from the 'die and the supports are tiltedisoasto.lowerthefront end of the. .die to plates I 22.

9 position the die with its axis at an angle. A vibrator mounted on the ejector then imparts vibrations to the die so that the casting will slide forwardly out of the die and into a trough for removal from the apparatus.

As shown in the drawings, the V-shaped su p-f ports for the die in the ejector comprise a pair of fixed plates I22 having slanting surfaces I23 (see Figs. 1, 3 and 6) forming one side of the V. The other side of the V is provided by a pair of movable plates I24. ,The fixed plates 122 constitute portions of a box-lilmframe in which the movable plates I24 are mounted. Such box-like frame is pivotally supported for tilting movement by a shaft I25 extending transversely to the axis of a die when positionedon the supports I22 and I24. The movement of the supports E22 and I26 on the shaft I25 provides for tilting the die so that the axis of the die extends forwardly and downwardly. Tilting movement of the frame is effected by a hydraulic actuator I29. Mounted in the box-like frame is a bar I26 lying directly under the die and having ablock I2'I at its forward end adapted to engage the lower portion of the front end of the die to hold the die against sliding movement when it is tilted. The bar I26 is slidably mounted in the box-like frame and a spring I28 is provided, tending to resiliently hold the bar in a fixed position relative to the frame. The bar I26 extends rearwardly from the boxlike frame and at its rear end carries a vibrator I30. .When the box-like frame is tilted'to tilt the die, the vibrator I30 is operated to cause vibration of the die, the vibratory motion being imparted to the bar I 26 carrying the block I2? at its front end and thus to the die. Since the die is held by the block. I21 against sliding movement, the casting willgradually slide forward out of the die and will be received in a forwardly and downwardly directed trough I3I located, at the front of the apparatus. Preferably, the trough i3I carries the finished casting to a conveyor I32, from which the finished castings may be removed.

After the casting has been removed from the dieand the die is tippedback to a horizontal position, the cap I is replaced on the die' and. thelatter is rolled off the ejector 22 and through a a swinging door I33 opening into the inter mediate section 22, the die then rolling onto the lowervtrack 24 for storage until it is ready to be admitted to the casting section 20. To this end, the movable plates we of the ejector are pivotally supported by a shaft I34 carried by the The plates I24 are normally held in araised position, as shown in Figs. 1 and 3, to hold the die in position in the ejector 21. For this purpose, the plates I24 are connected by an intermediate'plate I35, against which a holding cam I36 is positioned. Theholding cam I36 is mounted on a shatf I31 adapted to be operated by a hand crank MD. A torsion spring MI is mounted on the shaft I3? and tends to move the cam I36-to its upward position to hold the plates 2!? in diereceiving position. However, by turning the crank I40, the cam I36 may be lowered, permitting the plates I24 to swing about the shaft I34 and thus lowered to a horizontal position so that the die may be rolled through the door 33 onto the track 24.

The Storage section 22 One of the features of the invention is the I control possible with the present apparatus of the cooling rate of the castings. By such control, the metallurgical structure of the metal.

may be determined, a feature which is particularly important if the metal being cast is gray cast iron. The rate of cooling of the cast metal, of course, determines the character of the metal- 5 lurgical structure. The cooling depends upon a number of factors including the initial temperature of the molten metal, the insulating effect of the coating placed on the interior of the die, and the temperature of the die when introduced into the east section 2:]. The initial temperature of the molten metal can, of course, be controlled at' the melting furnace, and the insulating effect of the coating is dependent upon its composition and its characteristics when applied to the interior of the die. The initial temperature of the die before it is introduced into the casting section, however, can be controlled in the present apparatus. The rapidity with which heat is withdrawn from the casting after the dies and castings are moved into the storage section from the casting section is also controlled so that the casting is cooled sufiiciently for withdrawal from the die in the ejector section. The dies, when the apparatus is first started, are, of course, cold. and would have a considerable chilling eifect on the castings if the molten metal were poured into the dies at such temperature. It has been found, in correlating the die temperature to the other factors, that it is advantageous to have the dies, at the time of their introduction into the cast section 20, at a temperature ranging from 700 F. to 1000 F. To this end, the rear wall of the intermediate housing section is provided with a plurality of slots Ml (see Fig. 3) laterally spaced from each other a distance substantially equal to the diameter of the dies and positioned in the wall so that they'are substantially concentric with the axes of the dies located on the lower track 24. Mount- 40 ed on the rear wall of the housing are a plurality of gas burners, one being indicated at I42, for insertion through the slots IM to provide a flame directed into the interior of each die to initially heat the die. The gas burners I42, of course, ;,need, only be used when the apparatus is first started up, since thereafter the heat remaining in the dies from the casting will be suificient to maintain them at the desired temperature. To accurately determine the temperature of each aozgdie just before it enters the casting section 20,

a temperature recorder I43 (see Figs. 1 and 3) is mounted on top of the storage section 22 and is provided with a temperature-sensitive element I44 which may be lowered to a position imme- 5.35. diately over the die to record its temperature.

When the dies with the castings thereon are rolled off the'elevator 26 onto the track 23, there is, of course, a large amount of heat left in the casting. To remove this heat and bring the cast- Go f-ing to a temperature at which it is safe to remove it from the die, cool air is adapted to be the left end of the storage section 22, as viewed An air current entering through the in Fig. 1. intake M6 moves through the upper portion of castings. This air current is also utilized to control the temperature of the empty dies before entering 5 -diate partition I45 is provided with an opening the storage section to remove the heat from the the casting section. To this end, the interme- M1 at its right-hand end, as shown in Fig. 1,, to permit the air to be drawn downwardly into the lower portion of the storage section where the empty dies are stored. Thus, the air will pass over the empty dies and bring them to the desired temperature for admission to the casting section. From the lower portion of the storage section below the partition M5, the air is withdrawn by a flue 155 (see Figs. 1, 3 and4) which is provided with a fan for producing a forced flow of air. In order to control the rate of cooling of the castings in the upper part of the storage section and to control the temperature of the empty dies in the lower part of the storage section, a damper I52 is mounted in the flue I50 so that the rate of flow of air may thereby be controlled.

Brief description of operation From the foregoing, it will be apparent that empty dies are held in the lower portion of the storage section 22 ready for admission one at a time to the casting section 20. When a die is so admitted, it is placed in position on the rollers 33 and is rapidly rotated while first a spray coating is applied to the interior of the die by the nozzle 80, and thereafter molten metal is poured into the die by means of the pouring spout Hit. The die is kept spinning long enough for the metal therein to solidify. The rollers 33 are then stopped and the elevator 26 lifts the die from the rollers up to the level of the upper track 23 and rolls the die onto such track. While the die is held on the upper track I23, the air current passing through the storage section 22 removes heat from the casting in a controlled manner.

Thereafter, each die with its casting is rolled from the storage section 22 into the ejector section 2| and is lowered by the elevator 30 for placing on the ejector 21. There the die is tilted and, at the same time, vibrated so that the casting slides out forwardly and into the trough I3 I. The die is then rolled from the ejector 21 into the lower part of the storage section 22, where its temperature is brought to the desired point for re-introduction into the casting section 20.

I claim:

1. Apparatus for making centrifugal castings, comprising an elongated casing, die rotating means in one end of said casing for supporting a die during pouring of the metal, an ejector in the other'end of said casing for ejecting castings from the dies, a pair of tracks in said casing between said die rotating means and ejector, one above the other, with one track arranged for conveying dies with the castings therein from said die rotating means to the ejector, and the other track for conveying empty dies from the ejector to the die rotating means, a partition within said casing for enclosing the space about said other track, and means for circulating air through said space to control the temperature of the dies.-

2. Apparatus for making centrifugal castings, comprising a casing having casting means, an ejector, and a pair of tracks generally paralleling each other for conveying dies between said casting means and said ejector, a partition in said casing between the pair of tracks and having an opening therethrough to separate the interior of the casing into two spaces, and an air impeller for moving air first through the space on one side of said partition to cool the dies with the castings therein, then through said opening and through the space on the other side of said.

12 partition to control the temperature of. the empty dies.

3.. Apparatus for making centrifugal castings, comprising a casing having casting means, an ejector, and a pair of tracks generally paralleling each other and positioned one above the other, the upper track being arranged to convey dies with the castings therein from said casting means to said ejector, and the lower track being arranged to convey empty dies from said ejector to said casting means, a partition extending between the tracks to provide upper and lower compartments in the casing for the respective tracks and having an opening therethrough, a pair of doors for closing off the lower compartment from the casting means and said ejector respectively, and an air impeler for drawing a current of air through the upper compartment to cool the dies with the castings therein, then through said opening and through the lower compartment to cool the empty dies to a uniform temperature before they enter the casting means.

4. Appartus for making centrifugal castings, comprising a casing having casting means, an ejector, and a pair of tracks generally paralleling each other and positioned one above the other, the upper track being arranged to convey dies with the castings therein from said casting means to said ejector, and the lower track being arranged to convey empty dies from said ejector to said casting means, a partition extending between the tracks to provide upper and lower compartments for the respective tracks and having an opening therethrough, a pair of doors for closing off the lower compartment. from the casting means and ejector respectively, the upper compartment having an air inlet remote from said opening and the lower compartment havin an air outlet remote from said opening, and an air impelleradjacent said air outlet for drawing a current of air through the two compartments to control the temperature of the dies. 7

5. Apparatus for making centrifugal castings, comprising a casing having casting means and an ejector spaced from each other, the portion of the casing therebetween having a partition dividing the interior into two compartments with an. opening therebetween, one compartment having an air inlet and the other an airoutlet, a pair of tracks in the respective compartments for conveying, dies with the castings therein from the casting means to the ejector and empty dies from the ejector to the casting means, a flue con nected to said air outlet, a fan in said flue for drawing a current of air through the two compartments to cool the dies with the castings therein, and a damper in said flue forcontrolling the rate of flow of said current to cool the empty dies to a predetermined temperature before entering the casting means.

6. Apparatus according to claim 1 wherein said other track is inclined downwardly toward said .die rotating means, a door is slidably mounted for vertical movement in said casing adjacent said die rotating means and normally is held in its raised position extending across said other track, said door is adapted tobe lowered to permit the leading die to roll onto said die rotating means and the remaining dies to roll toward saiddoor, said other track has its end portion which supports said leading die more steeply inclined than the remainder of said other track to cause said leading die to roll onto said die rotating means, and a track member is movable, when the door is lowered, into position ROBERT C. MYERS.

References Citetl in the file of this patent UNITED STATES PATENTS Number Name Date Meehan Aug. 12, 1902 Johnston June 27, 1905 McWane Aug. 2, 1921 Prince June 27, 1922 Ladd Aug. 21, 1923 Moore et a1 Mar. 15, 1927 Moore Mar. 15, 1927 Moore Apr. 12, 1927 Pike Mar. 5, 1929 Redpath et a1 Mar. 5, 1929 Camerota May 13, 1930 McWane June 17, 1930 Moore et a1. Nov. 25, 1930 Number Number Name Date Mathieu June 16, 1931 Roberts Aug. 4, 1931 Barr et a1. May 29, 1934 Hunt et a1. Aug. 28, 1934 Wyant Oct. 16, 1934 Carrington Feb. 26, 1935 C'amerota June 9, 1936 Ridley et a1 Dec. 29, 1936 Camerota Mar. 23, 1937 Camerota July 27, 1937 Farr Jan. 3, 1939 Holmquist Dec. 23, 1941 Myers Apr. 7, 1942 Schuh et a1. Apr. 30, 1946 FOREIGN PATENTS Country Date Australia Sept. 27, 1951 

